Hydraulic cylinder



June 9, 1964 B. BUCKLEY 3,136,230

HYDRAULIC CYLINDER Filed Sept. 50, 1963 2 Sheets-Sheet 1 zu 3- 2O l" 2B 5o 21+ 3LP 2O 3 Fig'. Z

IO LH' +2 26 28 Bypcgy/gmy/ Arron/v5 ys June 9, 1964 B. BUcKLEY 3,136,230

HYDRAULIC CYLINDER Filed Sept. 30, 1963 2 Sheets-Sheet 2 United States Patent O 3,136,230 HYDRAULIC CYLINDER Bruce Buckley, Sioux City, Iowa, assignor to Prince Manufacturing Corporation, Sioux City, Iowa, a corporation of iowa Filed Sept. 30, 1963, Ser. No. 312,608 14 Claims. (Cl. 92-128) Hydraulic cylinders are widely used in many different fields of activities. Perhaps the most common difliculty associated with these hydraulic cylinders is the method of securing the cylinder heads to the cylinder. Many devices have been advanced which have not been altogether successful in meeting the above problem. One method of securing the cylinder Vhead to the cylinder is by a threaded insert. This threaded insert is very expensive to manufacture and when the cylinder is exposed to pressure, the threaded insert has a tendency to unthread. Another method of securing a cylinder head to the cylinder is by a snap ring device. These snap ring devices have a tendency to causeswelling of the cylinder and do not hold the cylinder head securely to the cylinder. The snap ring devices also have a tendency to squeeze into the center of the cylinder when pressure is applied to the device. In addition to the above shortcomings of the heretofore mentioned devices, said devices are diflicult to assemble and disassemble and usually need special tools for such assembly and disassembly. i

Therefore, an object of my invention is to provide a device which may be easily lassembled and disassembled without specialtools.

A further object of my invention is to provide a device which Will adequately hold extremely great thrust loads.

A furtherobject of my invention yis to provide a device which Will secure the cylinder head tightly to the cylinder.

A further object of my invention is to provide a cylinder head which is locked positively in place.

A further object of my invention is to provide a device which Will prevent a lock ring from squeezing in towardthe center of the cylinder.

A further object of my invention is to provide a device which is economical of manufacture, durable in use, and refined in appearance.

These and other objects will be apparent to those skilled in the art.

This invention consists in the construction, arrangements, and combination of the various parts of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, specilically pointed out in the claims, and illustrated in the `accompanying drawing, in which:

FIG. 1 is a perspective view ofthe device;

FIG. 2 is an enlarged scale cross-sectional view of the device as viewed on line 2-2 of FIG. l;

FIG. 3 is a partial side elevational view of the device, as viewed on line 3 3 of FIG. 2, with portions thereof cut away to more fully illustrate the assembled device; FIG. 4 is a partial side elevational view of the device with portions thereof cut away to illustrate the first step in disassembling the device;

FIG. 5 is a partial side elevationalview of the device with portions thereof cut away to illustrate the second step in disassembling the device;

FIG. 6 is a partial side elevational View of the device with portions thereof cut away to illustrate the third step in disassembling the device; y

FIG. 7 is a partial cross-sectional view of the device illustrating the third step in-disassembling the device;

FIG. 8 is a partial side elevational View of the device with portions thereof cut away to illustrate the fourth step in disassembling the device;

3,136,238 Patented .lune 9, 1964 ice ' FIG. 10 is a side elevational view of the locking ring.

I have used the numeral 10 to generally designate a hydraulic cylinder which hasa permanently normally closed end and anV open end. Hydraulic cylinder 10 includes a cylindrical casing 12, a iluid chamber 14, and ports 20 which are secured to casing 12 and in communication with uid chamber 14. Cylindrical casing 12 includes outer casing wall 16 and inner casing Wall 18. A piston (not shown) is slidably mounted Within cylindrical casing 12 and secured at one end to a piston rod 22. -A cylinder head 24 is slidably mounted on piston rod 22 within casing 12. Concentric grooves 26 in the inner casing wall 18 are located adjacent to ,the open end of casing 12 and are adapted to embrace locking ring 28, said locking ring 28 being comprised of ring segments 30, 32 and 34. Ring segment 30 includes straight parallel edges 50 and 52, an outer peripheral edge 54 and an inner peripheral edge 56. Ring segment 32 has one end thereof terminating in a straight edge 58 which is complementary to the straight edge of ring segment 30, an outer peripheral edge 60 and inner peripheral edge 62, the straight edge 50 being tangentially disposed with respect to the inner peripheral edge 62. Ring segment 34 has one end terminating in a straight edge 64 which is complementary to the straight edge 52 of ring segment 30, an outer peripheral edge 66 and an inner peripheral edge 68, the straight edge 64 being tangentially disposed with respect to the inner peripheral edge 68. Outer peripheral edges 54, 60 and 66 of ring segments 30, 32 and 34 are adapted to engage the concentric grooves 26 in casing 12. The structure of ring segments 30, 32 and 34 is such that when ring segments 32 and 34 are engaged in concentric grooves 26 of casing 12, ring segment 30 may be engaged in operating position or. disengaged from operating position without moving ring segments 32 and 34. The straight edge 58 of ring segment 32, being complementary to straight edge 50 of ring segment 30, and straight edge 64 of ring segment 34 being complementary to straight edge 52 of ring segment 30, permits engagement or disengagement of ring segment 30 without the necessity of moving ring segments 32 and 34. When ring segment 30 is engaged in operating position the abutment of straight edge 52 against straight edge 64 securely holds ring segments 32 and 34 in operating position.

A reduced diameter portion 36 of cylinder head 24 is adapted to engage locking ring 28, said engagement limiting the outwardly slidable movement of the cylinder head 24 and also serves to hold locking ring 28 in operating position. Reduced diameter portion. 36 has a concentric troduced into fluid chamber 14 through ports 20 by means of an external pump arrangement. The fluid causes the piston rod 22 to4 slidably move within the hydraulic cylinder. This slidable movement of the piston rod 22 may perform various tasks. The very heart of this device is in the structure of the cylinder head 24 and the means by which the cylinder head is secured to and removed from the hydraulic cylinder 10."

As liuid pressure is applied to the cylinder 24 from Within the fluid chamber 14, sealing rings 44 and 46 prevent the uidfrom escaping from the cylinder. The locking ring 2.3 which engages concentric grooves'26 in the inner wail 18 and also engages the reduced diameter portion 36 of cylinder head 24 prevents the cylinder head 24 from slidably moving outwardly. The retaining ring 40, which is mounted in concentric groove 3S of cylinder head 24,-embraces the outer edge of locking ring 28Vand prevents the cylinder head 24 from slidably moving inwardly.

To remove the cylinder head 24 from hydraulic cylinder lil the procedure isras follows, The retainingring 40 is removed from concentric groove 38 by means of a small screwdriver or other pointed device. Cylinder head 24 is then slidably moved inwardly in casing l2 until the cylinder head 24 clearsr locking ring 28. Locking ring 23 is then removed by moving ring segment 30 towards the-center of the v ring until the ringsegment 30 is disengaged from concentric grooves 26 in inner wall 13. Straight edge 55 of ring segment 32, which is complementary to straight edge Sti of ring segment 30, and straight edge'dl of ring segment 34, which Vis complementary to-straight edge 52 of ring segment .36, ypermits ring segment 3@ to belmoved toward the center of locking ringfZS without moving ring segments 32 and 34. The ringsegment 3i) is' then removed outwardly from the device. Ring segments 32 and Mare then independently disengaged from concentric grooves 26 by moving them in a direction towards the center of the cylinder and are then removed from'the device lthrough its open end. The cylinder'v head 24, piston -rod 22 and the pistonare removed from the casing and the unit is .then fully disassembled. The assembly of the unit would be accomplished by merely reversing the above "described steps of disassembly.

It is therefore seen that the device will accomplish at leastall of its stated objectives.

Some'changes may be made in the construction and arrangement of myvhydraulic cylinder without departing from the real spirit and purposeof my invention, and it is my intention to Vcover by my claims, any modified forms of structure or use of mechanical equivalents which may be reasonably kincluded within their scope.

I claim:

l. in a cylinder device, l

lan elongated hollow cylindrical casing having one kpermanently normally closed end and an open end,

a piston slidably mounted within said casing,

a piston rod secured to said piston,

a cylinder head slidably mounted on said piston rod within said casing,

a concentric groove within said cylinder casingadjacent to its open end,

a locking ring mounted in said groove and protruding therefrom to engage said cylinder head and to limit the outwardly slidable movementl of said cylinder head, A

said locking ring beingcomprised of a plurality ofrin- :dependent parts detachably held in said groove by said cylinder head,

and at least one fluid port on said casing and in communication with the interior thereof,

2. In a'cylinder device,

an elongated hollow cylindrical casing having one permanently normally closed end and an open end,

apiston slidably mounted within said casing,

a piston rod secured'to'said piston,

Y a cylinder head slidablymounted on saidpiston rod within said casing,

said cylinder head including at least -one groove eX- tending around the outer circumference of the cyl-v inder head with a sealing ring mounted therein,-

a bore passing substantially through the center of the cylinder head with `a plurality of grooves in the periphery thereof and sealing rings mounted therein,

a concentric groove'within said cylinder casing adjacent to its open end,

a lockingring mounted in said groove and `protruding therefrom to engage said cylinder head and to limit the outwardly vslidable movement of said cylinder head, l

said locking ring being comprised of a plurality of independent parts detachably held in said groove by said cylinder head,

land at least one fluid port on said casing and in communication with the interior thereof.

3. In a cylinder device,

an elongated hollow cylindrical casing having one permanently normally closed end and an open end,

a piston slidably mounted within said casing,

a'piston rod secured to said piston,

a cylinder `head slidably mounted on Vsaid piston rod within said'casing,

said cylinder head including at least one groove extending around the outer circumference of the cylinder head With 'a sealing ring mounted therein,`

a-bore passing substantially through the center of the cylinder head with a plurality of grooves in the periphery 'thereof and sealing rings mounted therein,

the lforward end of said cylinder head being of a reduced diameter and adapted to embrace the'inner edge of said locking ring with a groove extending around the circumference of the` reduced diameter portion ata right angle'to the longitudinal axis of the cylinder head, Vand a retaining ring mounted in said'groove and protruding therefromto engage said cylinder head and locking ring and to limit the inv Wardly slidable'movement of said cylinder head, a'concentric groove within said cylinder casing adjacent to its open end,

a lockingl ring mounted in said groove and protruding therefrom'to engage said cylinder head and to limit the outwardly slidable movementV of said cylinder head, Y Y l said locking ring beingV comprised of a plurality of independent parts detachably held in said groove by said cylinder head, and atleast one iluidiport on said casing and in communication with the interior thereof.

4. Thetstructure of claim 3 wherein the locking ring includes 'atleast three ring segments, the outer edges of which are adapted to be received in the concentric groove in said cylinder casing adjacent its open end, the inner edges of said locking ring segments being adapted to embrace the reduced diameter portion of the cylinder head.

' o'f said segments to be independently moved inwardly toward the center of said casing without moving 'said other segments when said cylinder head is withdrawn from engagement with said locking ring. v

6. The structure of claim 3 wherein the locking ring is substantially circular in shape when positioned in said concentric groove, said locking ring being comprised of three 'independent ring segments, and one of said ring segments engaging the other ring segments to maintain said other ring segments Within said concentric groove.

7. In va cylinder device, an elongated hollow cylindrical casing having one permanently normally closed end and an open end, a piston slidably mounted within said casing, apiston rod secured to said-piston, a cylinder head slidably mounted on said vpiston rod within said casing,` a concentricgroove within said cylinder casing adjacent to its openend, a locking ring mounted in said groove and protruding therefrom to engage said cylinder head and to limit the outwardly slidable movement of said cylinder head,

said locking ring being comprised of a plurality of independent parts detachably held in said groove by said cylinder head,

at least one fluid port on said casing and in communication with the interior thereof,

and a concentric groove on one end of said cylinder head with a retaining ring mounted therein and protruding therefrom, to engage said locking ring and to limit the inwardly slidable movement of said cylinder head.

8. In a cylinder device,

an elongated hollow cylindrical casing having one permanently normally closed end and an open end,

a piston slidably mounted within said casing,

a piston rod secured to said piston,

a cylinder head slidably mounted on said piston within said casing,

aconcentric groove in said cylinder casing adjacent to its open end, a locking ring mounted in said concentric groove and protruding therefrom to engage said cylinder head and to limit the outwardly slidable movement of said cylinder head,

said locking ring being comprised of a plurality of independent parts detachably held in said groove by said cylinder head,

and at least one fluid port on said casing and in communication with the interior thereof.

9. The structure of claim 8 wherein the locking ring includes at least three ring segments, the outer edges of which are adapted to be received in the concentric groove in said cylinder casing adjacent its open end.

10. The structure of claim 8 wherein said locking ring is comprised of three ring segments, one of said ring segments having straightparallel edges.

11. The structure of claim 8 wherein said locking ring is comprised of three ring segments, one of said ring segments having straight parallel edges; said other two ring segments having at least one end thereof terminating in a straight edge complementary to one of the two straight edges of said iirst ring segment.

12. The structure of claim 8 wherein said locking ring is comprised of three ring segments, one of said ring segments having straight parallel edges; said other two ring segments having straight parallel edges; said other two ring segments having atleast one end thereof terminating in a straight edge complementary to one of the two straight edges of said rst ring segment; said two other ring segments being substantially identical but being normally positioned in diametrically opposite and symmetrical positions Within said concentric groove.

13. The structure of claim 8 wherein said locking ring is comprised of three ring segments, one of said ring segments having straight parallel edges; said other two ring segments having straight parallel edges; said other two ring segments having at least one end thereof terminating in a straight edge complementary to one of the tWo straight edges of said first ring segment; said two other ring segments being substantially identical but being normally positioned in diametrically opposite and symmetrical positions within said concentric groove; said two other ring elements having inner circular peripheral edges with the straight end edges thereof being tangentially disposed with respect to said circular peripheral edges.

14. The structure of claim 8 wherein said locking ring is comprised of three ring segments, one of said ring segments having straight parallel edges and providing less than one-half the periphery of said locking ring.

References Cited in the file of this patent UNITED STATES PATENTS Gageby July 29, 1958 

1. IN A CYLINDER DEVICE, AN ELONGATED HOLLOW CYLINDRICAL CASING HAVING ONE PERMANENTLY NORMALLY CLOSED END AND AN OPEN END, A PISTON SLIDABLY MOUNTED WITHIN SAID CASING, A PISTON ROD SECURED TO SAID PISTON, A CYLINDER HEAD SLIDABLY MOUNTED ON SAID PISTON ROD WITHIN SAID CASING, A CONCENTRIC GROOVE WITHIN SAID CYLINDER CASING ADJACENT TO ITS OPEN END, A LOCKING RING MOUNTED IN SAID GROOVE AND PROTRUDING THEREFROM TO ENGAGE SAID CYLINDER HEAD AND TO LIMIT THE OUTWARDLY SLIDABLE MOVEMENT OF SAID CYLINDER HEAD, SAID LOCKING RING BEING COMPRISED OF A PLURALITY OF INDEPENDENT PARTS DETACHABLY HELD IN SAID GROOVE BY SAID CYLINDER HEAD, AND AT LEAST ONE FLUID PORT ON SAID CASING AND IN COMMUNICATION WITH THE INTERIOR THEREOF. 